Reviewed by the Evolve Health clinical team · 2026-09-30 · 1 min read
Poison ivy and poison oak grow throughout Texas — along trails, fence lines, creek banks, and even in suburban landscaping. Both contain urushiol, the oil that causes the infamous itchy rash. About 85% of people react to it.
Recognition
The old rhyme helps: "leaves of three, let it be." Poison ivy typically has three almond-shaped leaflets; poison oak's leaflets look oak-like with rounded lobes. Both can grow as vines, shrubs, or groundcover, and their appearance changes with the seasons — bare winter vines still carry the oil.
After exposure
If you think you've touched it, wash skin with soap and cool water as soon as possible — the oil can be removed before it binds. Wash clothing, shoes, garden tools, and pet fur separately; the oil stays active on surfaces for a long time and pets can carry it indoors on their coats.
The rash
The itchy, blistery rash usually appears within 12–72 hours in streaks or patches where the oil touched. It's uncomfortable but not contagious — you can't spread it by scratching, though the oil under fingernails can.
When to see us
See a provider for rashes on the face or genitals, widespread rashes, signs of infection (increasing pain, swelling, pus, or fever), or a rash that isn't improving after a couple of weeks.
Visit us
Evolve Health is at 2442 Lillian Miller Pkwy, Suite 115, Denton, TX 76205. Book online or call (940) 257-2002 to schedule a visit, in person or by video anywhere in Texas.
Need care for this?
Book an appointment online in under a minute, or call (940) 257-2002 — same-day appointments may be available.